EFEITO DA APLICAÇÃO SEQUENCIAL DE INSETICIDAS QUÍMICOS E MICROBIOLÓGICOS NO MANEJO DE Dalbulus maidis NA CULTURA DO MILHO
EFEITO DA APLICAÇÃO SEQUENCIAL DE INSETICIDAS QUÍMICOS E MICROBIOLÓGICOS NO MANEJO DE Dalbulus maidis NA CULTURA DO MILHO
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DOI: https://doi.org/10.22533/at.ed.88826300420
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Palavras-chave: Cigarrinha-do-milho, Controle químico, Controle Biológico.
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Keywords: Corn Leafhopper, Chemical control, Biological control.
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Abstract: Maintaining corn productivity through effective phytosanitary control is essential for achieving high yields. However, the crop constantly faces phytosanitary challenges related to insect pests, particularly the corn leafhopper (Dalbulus maidis). In this context, the use of microbiological insecticides can be an important alternative for the success of chemical treatments and the prevention of resistance by these insect pests in corn crops. Therefore, this study aimed to evaluate the effectiveness of corn leafhopper (Dalbulus maidis) control through the sequential application of chemical insecticides, combined or not with biological insecticides, as well as their interaction during the residual period. The trial was conducted at the experimental farm of the Federal Institute of Paraná (IFPR) - Ivaiporã Campus. The experimental design was a completely randomized block design, with treatments arranged in a 2x2+5 factorial arrangement. The first factor was the chemical insecticides acephate and the formulated mixture of isocycloseram + lambda-cyhalothrin; and the second factor was the microbiological insecticides Beauveria bassiana and Isaria fumosorosea. Additional treatments consisted of a control (no application) and the chemical and microbiological insecticides previously described, applied alone, and in combination, totaling nine treatments with five replicates each. The experiment was conducted in the field, with sequential sprayings performed 7 to 10 days apart, with treatments beginning upon the emergence of D. maidis in the experimental area. Control efficiency and residual period assessments were performed by directly counting insect pests present on the plants before and after application at the following intervals: 1, 3, and 7 DAA for control efficiency analysis, and 1, 3, 7, 14, 21, and 28 days for residual period evaluation. The experimental results showed that, despite the absence of statistically significant differences between treatments, those with chemical insecticides were more effective in both control and residual period, compared to exclusively microbiological treatments. Among the chemical treatments, acephate presented the best results in both applications. The biological treatments, Beauveria bassiana and Isaria fumosorosea, showed a delayed effect, with peak control at 7 days after application. The combination of Isaria fumosorosea with isocycloseram indicated greater persistent control, although it requires reapplications at short intervals due to its short residual period. Despite this, spraying microbiological insecticides resulted in a reduction of up to 50% in the leafhopper population, which may be useful in rotating active ingredients, reducing the selection pressure of chemical insecticides and contributing to integrated pest management.
- Murilo Fuentes Pelloso
- Kamila Aparecida Santos Fogaça
- Luiz Otavio Hencklein dos Santos
- Gabriel Justino Barbosa
- Igor Matheus Oliveira dos Santos
- Jhonatan Diego Cavalieri